This proposal is designed to study the metabolism and toxicity of N-(3, 5-dichlorophenyl) succinimide (3, 5-NDPS). Originally developed as an agricultural fungicide, 3, 5-NDPS was later found to produce a selective nephrotoxicity (proximal tubular necrosis) in rats. The underlying mechanism that results in toxicity is unknown, although 3, 5-NDPS is extensively metabolized in rats. An unusual aspect of this compound is that glutathione apparently potentiates, rather than ameliorates, the nephrotoxicity. Due to the highly selective nature of the damage produced, 3, 5-NDPS may be valuable as a model nephrotoxicant. It is therefore important to fully characterize the metabolic pathway of this compound. The information obtained from this project may be useful in determining what factors are important to the development of chemically-induced nephrotoxicity in humans and experimental animals. The long term goals of this project are to fully elucidate the metabolic pathway of 3, 5-NDPS in rats, and to determine which metabolite(s) contribute to the nephrotoxicity. The unusual role of glutathione in potentiating the toxicity will also be further investigated. Ultimately, the studies will be extended to analogues of 3, 5-NDPS. To accomplish these goals, the following specific aims have been developed: synthesize the known and potential metabolites of 3, 5-NDPs; administer the synthetic metabolites to rats and measure nephrotoxicity; develop and HPLC-based assay to detect and quantitate the production of the metabolites form radiolabelled 3, 5-NDPS both in vitro and in vivo; and to determine what structural features are responsible for the nephrotoxicity of 3, 5-NDPS. Strategies to synthesize 3, 5-NDPS and it metabolites (reported and proposed) have been developed. Preliminary attempts to develop an HPLC-based assay to separate 3, 5-NDPS from the available metabolites have been encouraging. the metabolic and toxicity studies will begin with the completion of these first two steps.